// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_
#define CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_

#include <stdint.h>

#include <memory>

#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_vector.h"
#include "base/numerics/safe_math.h"
#include "content/common/content_export.h"
#include "ppapi/c/pp_codecs.h"
#include "ppapi/host/host_message_context.h"
#include "ppapi/host/resource_host.h"
#include "ppapi/proxy/resource_message_params.h"
#include "ppapi/proxy/serialized_structs.h"
#include "ppapi/shared_impl/media_stream_buffer_manager.h"

namespace content {

class RendererPpapiHost;

class CONTENT_EXPORT PepperAudioEncoderHost
    : public ppapi::host::ResourceHost,
      public ppapi::MediaStreamBufferManager::Delegate {
public:
    PepperAudioEncoderHost(RendererPpapiHost* host,
        PP_Instance instance,
        PP_Resource resource);
    ~PepperAudioEncoderHost() override;

private:
    class AudioEncoderImpl;

    // ResourceHost implementation.
    int32_t OnResourceMessageReceived(
        const IPC::Message& msg,
        ppapi::host::HostMessageContext* context) override;

    int32_t OnHostMsgGetSupportedProfiles(
        ppapi::host::HostMessageContext* context);
    int32_t OnHostMsgInitialize(
        ppapi::host::HostMessageContext* context,
        const ppapi::proxy::PPB_AudioEncodeParameters& parameters);
    int32_t OnHostMsgGetAudioBuffers(ppapi::host::HostMessageContext* context);
    int32_t OnHostMsgEncode(ppapi::host::HostMessageContext* context,
        int32_t buffer_id);
    int32_t OnHostMsgRecycleBitstreamBuffer(
        ppapi::host::HostMessageContext* context,
        int32_t buffer_id);
    int32_t OnHostMsgRequestBitrateChange(
        ppapi::host::HostMessageContext* context,
        uint32_t bitrate);
    int32_t OnHostMsgClose(ppapi::host::HostMessageContext* context);

    void GetSupportedProfiles(std::vector<PP_AudioProfileDescription>* profiles);
    bool IsInitializationValid(
        const ppapi::proxy::PPB_AudioEncodeParameters& parameters);
    bool AllocateBuffers(
        const ppapi::proxy::PPB_AudioEncodeParameters& parameters,
        int32_t samples_per_frame);
    void DoEncode();
    void BitstreamBufferReady(int32_t audio_buffer_id,
        int32_t bitstream_buffer_id,
        int32_t size);
    void NotifyPepperError(int32_t error);
    void Close();

    static void StopAudioEncoder(
        std::unique_ptr<AudioEncoderImpl> encoder,
        std::unique_ptr<ppapi::MediaStreamBufferManager> audio_buffer_manager,
        std::unique_ptr<ppapi::MediaStreamBufferManager>
            bitstream_buffer_manager);

    // Non-owning pointer.
    RendererPpapiHost* renderer_ppapi_host_;

    // Whether the encoder has been successfully initialized.
    bool initialized_;

    // Last error reported by the encoder.
    // This represents the current error state of the encoder, i.e. PP_OK
    // normally, or a Pepper error code if the encoder is uninitialized,
    // has been notified of an encoder error, has encountered some
    // other unrecoverable error, or has been closed by the plugin.
    // This field is checked in most message handlers to decide whether
    // operations should proceed or fail.
    int32_t encoder_last_error_;

    // Manages buffers containing audio samples from the plugin.
    std::unique_ptr<ppapi::MediaStreamBufferManager> audio_buffer_manager_;

    // Manages buffers containing encoded audio from the browser.
    std::unique_ptr<ppapi::MediaStreamBufferManager> bitstream_buffer_manager_;

    // Media task runner used to run the encoder.
    scoped_refptr<base::SingleThreadTaskRunner> media_task_runner_;

    // The encoder actually doing the work.
    std::unique_ptr<AudioEncoderImpl> encoder_;

    base::WeakPtrFactory<PepperAudioEncoderHost> weak_ptr_factory_;

    DISALLOW_COPY_AND_ASSIGN(PepperAudioEncoderHost);
};

} // namespace content

#endif // CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_ENCODER_HOST_H_
